84 results on '"Janda, P."'
Search Results
2. The Association of Oxygen Delivery and Transfusion on Cardiopulmonary Bypass with Acute Kidney Injury.
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Engoren, Milo, Janda, Allison, Heung, Michael, Sturmer, David, Likosky, Donald S., Hawkins, Robert B., Do-Nguyen, Chi Chi, and Mathis, Michael
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To estimate whether the association of transfusion and acute kidney injury (AKI) has a threshold of oxygen delivery below which transfusion is beneficial but above which it is harmful. Retrospective study Cardiovascular operating room and intensive care unit Patients undergoing cardiac surgery with continuous oxygen delivery monitoring during cardiopulmonary bypass None Logistic regression was used to estimate the associations between oxygen delivery (mean, cumulative deficit, and bands of oxygen delivery), transfusion, and their interaction and AKI. A subgroup analysis of transfused and nontransfused patients with exact matching on cumulative oxygen deficit and time on bypass with adjustment for propensity to receive a transfusion using logistic regression. Nine hundred ninety-one of 4,203 patients developed AKI within 7 days. After adjustment for confounders, lower mean oxygen delivery (odds ratio [OR], 0.968; 95% confidence interval [CI], 0.949-0.988; p = 0.002) and transfusions (OR, 1.442; 95% CI, 1.077, 1.932; p = 0.014) were associated with increased odds of AKI by 7 days. As oxygen delivery decreased, the risk of AKI increased, with the slope of the OR steeper at <160 mL/m
2 /min. In the subgroup analysis, matched transfused patients were more likely than matched nontransfused patients to develop AKI (45% [n = 145] v 31% [n = 101]; p < 0.001). However, after propensity score adjustment, the difference was nonsignificant (OR, 1.181; 95% CI, 0.796-1.752; p = 0.406). We found a nonlinear relationship between oxygen delivery and AKI. We found no level of oxygen delivery at which transfusion was associated with a decreased risk of AKI. [ABSTRACT FROM AUTHOR]- Published
- 2024
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3. Reconstruction of SnO2 after cathodic polarization of FTO films - A simple way of fabricating orthorhombic SnO2
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Krýsová, H., Neumann-Spallart, M., Tarábková, H., Paušová, Š., Janda, P., Maixner, J., Kavan, L., and Krýsa, J.
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- 2021
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4. Climatic drivers of Picea growth differ during recruitment and interact with disturbance severity to influence rates of canopy replacement
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Saulnier, M., Schurman, J., Vostarek, O., Rydval, M., Pettit, J., Trotsiuk, V., Janda, P., Bače, R., Björklund, J., and Svoboda, M.
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- 2020
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5. Misfit simulation on implant prostheses with different combinations of engaging and nonengaging titanium bases. Part 2: Screw resistance test.
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Rutkunas, Vygandas, Dirse, Julius, Kules, Daniel, Mischitz, Ingrida, Larsson, Christel, and Janda, Martin
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Prosthesis fit is 1 of the main factors influencing the success and survival of an implant-supported screw-retained restoration. However, scientific validation of the performance of engaging and nonengaging components in a fixed partial denture (FPD) and the effect of their combinations on the fit of FPDs is lacking. The screw resistance test has been used for the fit assessment of screw-retained FPDs. However, objective assessments by using analog and digital devices are now available. The purpose of this in vitro study was to investigate the effect of engaging and nonengaging components on the fit of screw-retained frameworks, supported by 2 conical connection implants with simulated vertical and horizontal misfits, by performing 2 different screw resistance tests (analog and digital). Thirty 2-implant-supported bar-shaped zirconia frameworks cemented on two 2-mm titanium bases were fabricated and divided into 3 groups (n=10) according to different abutment combinations: both engaging, engaging and nonengaging, both nonengaging. The fit of each framework was tested on the control cast and on 6 definitive casts simulating 50-, 100-, and 150-μm vertical and 35-, 70-, and 100-μm horizontal misfit levels. The abutment screws were tightened on each implant, and the screw rotation angle was measured both digitally, with a custom-made digital torque wrench and a computer software program, and conventionally, with an analog torque wrench and protractor. Clearly ill-fitting specimens were excluded. The data were statistically analyzed by 1-way analysis of variance (ANOVA) and the Tukey post hoc test (α=.05). Both engaging specimens on the 100-μm horizontal misfit group and on all vertical misfit groups were clearly ill-fitting and excluded. Statistically significant differences among groups with different combinations of abutments were found (P <.05). The engaging abutments had a higher angle of rotation than the nonengaging abutments on all casts. In the horizontal misfit group, both engaging specimens had the highest angle of rotation, followed by engaging and nonengaging and both engaging specimens. In the vertical misfit group, the engaging and nonengaging specimens had the highest angle of rotation on the side of the engaging abutment. The angle of rotation increased with the increasing level of misfit. Both nonengaging frameworks showed superiority in misfit tolerance, as the angle of rotation was lower than that of the engaging and nonengaging and both engaging frameworks. Conventional and digital torque wrenches showed similar results. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Rescuing the right ventricle: A conceptual framework to target new interventions for patients receiving a durable left ventricular assist device.
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Pienta, Michael J., Noly, Pierre-Emmanuel, Janda, Allison M., Tang, Paul C., Bitar, Abbas, Mathis, Michael R., Aaronson, Keith D., Pagani, Francis D., and Likosky, Donald S.
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- 2023
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7. Exploring the multiple drivers of alpha and beta-diversity dynamics in Europe's primary forests: Informing conservation strategies.
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Ferenčík, Matej, Hofmeister, Jeňýk, Mikoláš, Martin, Buechling, Arne, Gloor, Rhiannon, Kozák, Daniel, Topercer, Ján, Pavlin, Jakob, Petriţan, Ion Catãlin, Bače, Radek, Dúhová, Daniela, Frankovič, Michal, Janda, Pavel, Kameniar, Ondrej, Markuljaková, Katarína, Mejstřík, Marek, Pardus, Ivo, Wiezik, Michal, Wieziková, Adela, and Svoboda, Miroslav
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BIOLOGICAL extinction ,ENVIRONMENTAL degradation ,FOREST conservation ,CONSERVATION projects (Natural resources) ,BIODIVERSITY conservation ,FOREST biodiversity - Abstract
Addressing the scope of biodiversity loss is a societal issue. However, consensus regarding effective management practices to attenuate species extinction is lacking. An assessment of spatial variation in species assemblages (beta-diversity) provides a promising framework for informing forest landscape planning. Within the context of recent European Union biodiversity conservation goals, this research demonstrates an application of beta-diversity theory to understand spatial patterns in the distribution of a suite of environmentally-sensitive taxa within Europe's remaining best-preserved primary forests. We sampled the local community composition (alpha-diversity) of four taxonomic groups (birds, epiphytic and epixylic lichens, saproxylic beetles, and deadwood-inhabiting fungi) to estimate corresponding levels of beta-diversity, as well as the underlying spatial components of nestedness and turnover. To identify particularly sensitive sites on the landscape that are potentially important for multiple species, we assessed beta-diversity congruence among the taxonomic groups. To elucidate critical abiotic factors and resource attributes underpinning biodiversity patterns, we regressed observed levels of local species richness against selected habitat variables. Results show that levels of beta-diversity were high and predominantly driven by spatial turnover, particularly for dispersal-limited organisms having relationships with deadwood. Beta-diversity was lowest for the avian group, reflecting their mobility. The lichen and fungal groups were correlated in terms of beta-diversity and turnover likely due to similar resource requirements. Variation in deadwood attributes (volume, decay stage) was significantly related to the local species richness of beetle and lichen communities. We identified occurrences of several threatened (red-listed) species that were similarly associated with deadwood substrates. We suggest that the beta-diversity patterns and habitat associations revealed by our analyses provide baseline data for comparison with managed systems. In particular, our findings highlight the importance of dead trees and logs for biodiversity conservation, suggesting a need for management strategies that retain an abundant and diverse supply of deadwood in forested landscapes. • Levels of beta-diversity were high and predominantly driven by spatial turnover. • Each primary forest fragment had a unique species composition. • Spatial turnover was significantly higher than nestedness. • Forest maturity significantly influenced the occurrence of red-listed species. • Deadwood variability is more critical for forest-dwelling taxa than its volume. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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8. 52470 Nevus counting and reporting methodologies in general population studies: A systematic review.
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Ashley, Daniel, Jayasinghe, Dilki, Naranpanawa, Nathasha, Ingvar, Åsa, Betz-Stablein, Brigid, Soyer, Peter, and Janda, Monika
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- 2024
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9. Past disturbances shape present tree size distribution in European temperate primary beech-dominated forests.
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Rodrigo, Ruffy M., Pettit, Joseph L., Janda, Pavel, Pavlin, Jakob, Ralhan, Dheeraj, Kozak, Daniel, Matula, Radim, Marchand, William, Bače, Radek, Dušátko, Martin, Kníř, Tomás, Frankovič, Michal, Mikoláš, Martin, Hofmeister, Jeňýk, Roibu, Cătălin-Constantin, Saulnier, Melanie, and Svoboda, Miroslav
- Abstract
Natural disturbances play a crucial role in shaping forest structural dynamics, directly influencing stand structural heterogeneity. In European forests, disturbances occur across varying scales, from small patches to entire landscapes, significantly affecting ecosystem dynamics. However, detailed information on historical disturbances and their specific effects on forest structure, particularly tree size distributions in primary mountain forests, remains limited. With global change altering the severity and frequency of these disturbances, understanding their long-term impact has become increasingly critical for forest management and conservation. We addressed two main questions: (1) Is there variability in tree size distributions at both the plot and stand level? and (2) which specific aspects of disturbance regimes, such as severity and timing, are most influential in shaping these distributions? To address these questions, we analyzed data from 11,755 trees across 23 primary European beech forest stands in the Carpathian Mountains of Romania (139 plots) and Slovakia (99 plots). Using linear mixed-effects models, we assessed how historical disturbances have influenced current tree size distributions. Our results showed that tree size distributions across the Carpathians show variability, with the most common pattern being close to a reverse-J shape, indicative of uneven-aged forest structures. Modelling analyses revealed that disturbance severity and timing are key factors influencing present tree size distribution patterns at small scales in the Carpathian Mountains. High-severity disturbances generally result in unimodal or bimodal distributions, while low-severity disturbances are associated with reverse-J shaped patterns. Specifically, at the plot level (small scale), we observed that last disturbance severity, maximum disturbance severity, and time since the last disturbance all significantly impacted tree size distributions driving them away from a reverse-J shape. Finally, linear mixed-effects modeling revealed that disturbance severity, time since the last disturbance and the interaction between the two were the most influential factors shaping present tree size distributions. Our findings highlight the dynamic nature of forest ecosystems, emphasizing the critical role of historical disturbances in shaping present tree structure and the long-term development of forest stands. • Primary beech-dominated forests exhibit complex patterns in tree size distribution. • Disturbance severity significantly influences present tree size distribution. • The interaction between disturbance severity and timing is crucial in shaping forest structure [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Working Together to Improve Type 2 Diabetes Care: A Participatory Design Project to Address Identified Needs of People With Diabetes and Their Health-care Professionals.
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Catapan, Soraia de Camargo, Vasconcelos Silva, Carina, Bird, Dominique, Janda, Monika, Gray, Len, Maunder, Lisbeth, Clemensen, Jane, Menon, Anish, and Russell, Anthony
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- 2024
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11. Description of collaborative, fee-for-service, office-based, pharmacist-directed medical cannabis therapy management service for patients with chronic pain.
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Bellnier, Terrance J., Brown, Geoffrey W., Ortega, Tulio, Janda, Maria, and Miskowitz, Kyle
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MEDICAL marijuana ,CHRONIC pain ,PATIENT satisfaction ,PAIN clinics ,FEE for service (Medical fees) ,THERAPEUTICS - Abstract
Background: Treatment with medical cannabis (MC) in the United States tends to be patient-driven in nature despite evidence that suggests that patients have remarkably poor knowledge on the medical use of this treatment modality.Objective: To develop and pilot a collaborative, fee-for-service (FFS), office-based, pharmacist-directed MC therapy management (MCTM) service for patients suffering chronic pain.Practice Description: A collaborative, FFS, office-based, pharmacist-directed MCTM service where patients are seen after a physician deems them suitable for treatment with MC. The pharmacist designs the initial treatment regimen by selecting a formulation, dose, route, and frequency of administration and then manages ongoing therapy by making regimen changes based on the patient's response, adverse effects, and financial concerns.Practice Innovation: The creation of a specialized service where a registered MC pharmacist is positioned in a collaborating provider's office and sees patients face-to-face for the provision of MCTM services.Evaluation Methods: Patient retention, revenue generated, and ability to replicate the service were evaluated. Patient satisfaction was assessed by collecting subjective feedback on the service.Results: The pilot site that developed the service has seen 133 patients from 2016 to 2021 and has retained 89% of patients after 5 years of quarterly appointments. Patients appear willing to pay out of pocket for the service, and the revenue generated covers the pharmacist's and collaborating physician's time as well as additional overhead. The service has been replicated at 2 additional sites, and patient feedback has been positive.Conclusions: MCTM is another useful pharmacist service that patients are willing to pay for. MCTM services decrease the collaborating provider's workload while still allowing them to offer their patients personalized treatment with MC. In our experience, the service retains patients, generates enough revenue to cover costs, can be replicated, and is well received by patients. [ABSTRACT FROM AUTHOR]- Published
- 2022
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12. Light propagation in planar optical waveguides made of silicon nanocrystals buried in silica glass
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Janda, P., Valenta, J., Ostatnický, T., Pelant, I., and Elliman, R.G.
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- 2006
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13. Silicon nanocrystals in silica—Novel active waveguides for nanophotonics
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Janda, P., Valenta, J., Ostatnický, T., Skopalová, E., Pelant, I., Elliman, R.G., and Tomasiunas, R.
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- 2006
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14. Colloidal suspensions of silicon nanocrystals: from single nanocrystals to photonic structures
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Valenta, J., Janda, P., Dohnalová, K., Nižňansky, D., Vácha, F., and Linnros, J.
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- 2005
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15. The impact of team familiarity on intra and postoperative cardiac surgical outcomes.
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Mathis, Michael R., Yule, Steven, Wu, Xiaoting, Dias, Roger D., Janda, Allison M., Krein, Sarah L., Manojlovich, Milisa, Caldwell, Matthew D., Stakich-Alpirez, Korana, Zhang, Min, Corso, Jason, Louis, Nathan, Xu, Tongbo, Wolverton, Jeremy, Pagani, Francis D., and Likosky, Donald S.
- Abstract
Familiarity among cardiac surgery team members may be an important contributor to better outcomes and thus serve as a target for enhancing outcomes. Adult cardiac surgical procedures (n = 4,445) involving intraoperative providers were evaluated at a tertiary hospital between 2016 and 2020. Team familiarity (mean of prior cardiac surgeries performed by participating surgeon/nonsurgeon pairs within 2 years before the operation) were regressed on cardiopulmonary bypass duration (primary—an intraoperative measure of care efficiency) and postoperative complication outcomes (major morbidity, mortality), adjusting for provider experience, surgeon 2-year case volume before the surgery, case start time, weekday, and perioperative risk factors. The relationship between team familiarity and outcomes was assessed across predicted risk strata. Median (interquartile range) cardiopulmonary bypass duration was 132 (91–192) minutes, and 698 (15.7%) patients developed major postoperative morbidity. The relationship between team familiarity and cardiopulmonary bypass duration significantly differed across predicted risk strata (P =.0001). High (relative to low) team familiarity was associated with reduced cardiopulmonary bypass duration for medium-risk (–24 minutes) and high-risk (–27 minutes) patients. Increasing team familiarity was not significantly associated with the odds of major morbidity and mortality. Team familiarity, which was predictive of improved intraoperative efficiency without compromising major postoperative outcomes, may serve as a novel quality improvement target in the setting of cardiac surgery. [ABSTRACT FROM AUTHOR]
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- 2021
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16. Changes in physiology, gene expression and ethylene biosynthesis in MDMV-infected sweet corn primed by small RNA pre-treatment.
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Balassa, Kinga, Balassa, György, Gondor, Orsolya Kinga, Janda, Tibor, Almási, Asztéria, and Rudnóy, Szabolcs
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The physiological condition of plants is significantly affected by viral infections. Viral proliferation occurs at the expense of the energy and protein stores in infected plant cells. At the same time, plants invest much of their remaining resources in the fight against infection, making them even less capable of normal growth processes. Thus, the slowdown in the development and growth processes of plants leads to a large-scale decrease in plant biomass and yields, which may be a perceptible problem even at the level of the national economy. One form of protection against viral infections is treatment with small interfering RNA (siRNA) molecules, which can directly reduce the amount of virus that multiplies in plant cells by enhancing the process of highly conserved RNA interference in plants. The present work demonstrated how pre-treatment with siRNA may provide protection against MDMV (Maize dwarf mosaic virus) infection in sweet corn (Zea mays cv. saccharata var. Honey Koern). In addition to monitoring the physiological condition of the maize plants, the accumulation of the virus in young leaves was examined, parallel, with changes in the plant RNA interference system and the ethylene (ET) biosynthetic pathway. The siRNA pre-treatment activated the plant antiviral defence system, thus significantly reducing viral RNA and coat protein levels in the youngest leaves of the plants. The lower initial amount of virus meant a weaker stress load, which allowed the plants to devote more energy to their growth and development. In contrast, small RNA pre-treatment did not initially have a significant effect on the ET biosynthetic pathway, but later a significant decrease was observed both in the level of transcription of genes responsible for ET production and, in the amount of ACC (1-aminocyclopropane-1-carboxylic acid) metabolite. The significantly better physiological condition, enhanced RNAi response and lower quantity of virus particles in siRNA pretreated plants, suggested that siRNA pre-treatment stimulated the antiviral defence mechanisms in MDMV infected plants. In addition, the consistently lower ACC content of the plants pre-treated with siRNA suggest that ET does not significantly contribute to the successful defence in this maize hybrid type against MDMV. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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17. Reduced Echocardiographic Inotropy Index after Cardiopulmonary Bypass Is Associated With Complications After Cardiac Surgery: An Institutional Outcomes Study.
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Mathis, Michael R., Duggal, Neal M., Janda, Allison M., Fennema, Jordan L., Yang, Bo, Pagani, Francis D., Maile, Michael D., Hofer, Ryan E., Jewell, Elizabeth S., and Engoren, Milo C.
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Despite advances in echocardiography and hemodynamic monitoring, limited progress has been made to effectively quantify left ventricular function during cardiac surgery. Traditional measures, including left ventricular ejection fraction (LVEF) and cardiac index, remain dependent on loading conditions; more complex measures remain impractical in a dynamic surgical setting. However, the Smith-Madigan Inotropy Index (SMII) and potential-to-kinetic energy ratio (PKR) offer promise as measures calculable during cardiac surgery and potentially predictive of outcomes. Using echocardiographic and hemodynamic monitoring data, the authors aimed to calculate SMII and PKR values after cardiopulmonary bypass and understand associations with postoperative outcomes, adjusting for previously identified risk factors. Observational cohort study. Tertiary care academic hospital. The study comprised 189 elective adult cardiac surgical procedures from 2015-2016. None. The primary outcome was postoperative mortality or organ system complication (stroke, prolonged ventilation, reintubation, cardiac arrest, acute kidney injury, new-onset atrial fibrillation). After adjustment, SMII <0.83 W/m
2 independently predicted the primary outcome (adjusted odds ratio 2.19, 95% confidence interval 1.08-4.42); whereas PKR, LVEF, and cardiac index demonstrated no associations. When SMII and PKR were incorporated into a EuroSCORE II risk model, predictive performance improved (net reclassification index improvement 0.457; p = 0.001); whereas a model incorporating LVEF and cardiac index demonstrated no improvement (0.130; p = 0.318). The present study demonstrated that SMII, but not PKR, as a measure of cardiac function was associated with major complications. The study's data may guide investigations of more suitable perioperative goal-directed therapies to reduce complications after cardiac surgery. [ABSTRACT FROM AUTHOR]- Published
- 2021
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18. Δ-9-tetrahydrocannabinol dose increase leads to warfarin drug interaction and elevated INR.
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Brown, Geoffrey W., Bellnier, Terrance J., Janda, Maria, and Miskowitz, Kyle
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DRUG interactions ,DRUG side effects ,WARFARIN ,INTERNATIONAL normalized ratio ,CYTOCHROME P-450 - Abstract
Objective: We have reported a case of a drug-drug interaction (DDI) involving warfarin and Δ-9-tetrahydrocannabinol (THC) that resulted in a supratherapeutic international normalized ratio (INR) level. The purpose of this case report is to highlight the possibility of a pharmacokinetic DDI between THC and warfarin.Case Summary: A 67-year-old Caucasian man suffering from chronic pain presented to a dispensary in Buffalo, NY, for a refill of his medical cannabis (MC). The patient asked to speak with the pharmacist, and during their discussion the patient stated that he had a supratherapeutic INR level of 5.2 measured at home with a self-test device. The patient had no evidence of bleeding, and administration of warfarin was held for 2 days before the INR level returned to a normal range. The supratherapeutic level occurred when the patient was self-titrating his dose of THC and scored an 8, or "probable," on the Naranjo Adverse Drug Effect Probability Scale.Practice Implications: Warfarin and cannabinoids such as THC are both metabolized by cytochrome P450 (CYP) isozymes present in the liver and gastrointestinal tract. In the case described, a dose increase of 7.35 mg THC preceded an INR elevation of 5.2, but did not result in any bleeding. These observations are suggestive of a DDI involving warfarin and THC. Clinicians involved with MC should have adequate knowledge of the drugs that act as substrates, inhibitors, and inducers of CYP enzymes, including the major cannabinoids. [ABSTRACT FROM AUTHOR]- Published
- 2021
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19. Navigating community engagement in participatory modeling of food systems.
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Wentworth, Chelsea, Arroyo, Mariana Torres, Lembi, Rafael Cavalcanti, Feingold, Beth J., Freedman, Darcy, Gray, Steven, Hodbod, Jennifer, Jablonski, Becca B.R., Janda-Thomte, Kathryn M., Lemoine, Pablo, Nielsen, Aida, Romeiko, Xiaobo Xue, Salvo, Deborah, Olabisi, Laura Schmitt, van den Berg, Alexandra E., and Yamoah, Owusua
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NUTRITION policy ,COVID-19 pandemic ,RESEARCH personnel ,TRUST ,LOCAL knowledge - Abstract
This paper describes the participatory modeling experiences of five discrete teams across the U.S. working to develop models of food systems to identify leverage points and policies to induce food system transformation. Collaboration between academic and community partners within these individual modeling processes enables teams to address food systems complexity, integrate scientific evidence and local knowledge into models, while improving a model's credibility and accessibility for policymaking. While tools for facilitating participatory modeling are becoming more available, there is scant discussion on the practicalities of community engagement processes, including how teams respond to the needs of partners, navigate challenges that arise during projects, and communicate results. Synthesizing results from five independent teams in Albany, New York; Austin, Texas; Cleveland, Ohio; Denver, Colorado; and Flint, Michigan, this paper provides an overview of each team's approach to community engagement for participatory modeling of food systems. Analysis of engagement strategies across these five teams revealed four essential components to successful participatory modeling projects: 1) building research in collaboration with partners from the onset, 2) developing awareness of the challenges of community-researcher partnerships, 3) supporting transparent communication, and 4) promoting justice and trust through accessible dissemination processes. We emphasize that there is no single best approach to participatory modeling with community partners, rather that researchers need to understand and respond to various stakeholder needs. While each team faced challenges to the engagement process, including responding to the COVID-19 pandemic, our findings reveal important considerations for research in participatory modeling for food system policy. • Participatory modeling is useful to bridge academic knowledge and policy-making. • Immediate food access and lasting climate impacts of food systems challenges engaged modeling. • We synthesize lessons from five independent projects on participatory modeling of food systems. • Researchers must be responsive to community assets to produce policy relevant results. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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20. An outreach telephone program for advanced melanoma supportive care: Acceptability and feasibility.
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Fox, Jennifer, Janda, Monika, Bennett, Fiona, and Langbecker, Danette
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People with advanced melanoma face an uncertain trajectory as new treatments now have the potential to provide longer-term survival for some. However, the disease course is variable and unpredictable, with many expressing a need for better supportive care. This study aimed to investigate the acceptability and feasibility of extending an existing melanoma-specific self-referral or 'passive' telephone consultation support service to an 'active' outreach call to offer a supportive care program tailored to the needs of the patient. Participants were enrolled by their oncology nurse into a single group pre-post intervention study. Participants received an outreach telephone call focused on knowledge and skill development. Participants completed questionnaires at baseline and four weeks post-intervention. Post-intervention interviews with patients and involved staff were used to explore acceptability and feasibility of the outreach service call. Of 18 participants approached, 15 enrolled and 14 received the intervention. Staff time required for intervention delivery provided evidence for feasibility. Participants perceived the intervention as acceptable, and beneficial. In interviews, having someone with melanoma-specific knowledge to talk with was a key benefit of the outreach call program. Many participants expressed that they would have wished to receive the outreach call at an earlier stage, for example at the time of recurrence of/progression to advanced melanoma. Extending an existing self-referral support service model to use a more 'active' outreach approach is acceptable and feasible. The next step in the evaluation process for this intervention is a randomised controlled trial to determine effectiveness and cost-effectiveness. • Immune and targeted therapies for advanced melanoma may provide longer term survival for some. • The advanced melanoma disease course is unpredictable with a need for better supportive care. • An 'active' outreach call to offer a tailored supportive care program is acceptable and feasible. • An outreach call at an earlier stage of an advanced melanoma diagnosis is preferable. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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21. Drivers of basal area variation across primary late-successional Picea abies forests of the Carpathian Mountains.
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Janda, Pavel, Tepley, Alan J., Schurman, Jonathan S., Brabec, Marek, Nagel, Thomas A., Bače, Radek, Begovič, Krešimir, Chaskovskyy, Oleh, Čada, Vojtěch, Dušátko, Martin, Frankovič, Michal, Kameniar, Ondrej, Kozák, Daniel, Lábusová, Jana, Langbehn, Thomas, Málek, Jakub, Mikoláš, Martin, Nováková, Markéta H., Svobodová, Kristýna, and Synek, Michal
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BASAL area (Forestry) ,NORWAY spruce ,ECOLOGICAL disturbances ,FOREST biomass ,CARBON sequestration in forests ,ECOLOGICAL heterogeneity ,SPATIAL variation - Abstract
Highlights • Basal area (BA) was correlated with macroclimatic gradients along the Carpathians. • Fine-scale variation of BA is linked to local disturbances. • Recent stationarity in stand BA implied despite disturbance related variability. • Instances of high recent mortality may indicate a departure from stationarity. Abstract Disentangling the importance of developmental vs. environmental drivers of variation in forest biomass is key to predicting the future of forest carbon sequestration. At coarse scales, forest biomass is likely to vary along major climatic and physiographic gradients. Natural disturbance occurs along these broad biophysical gradients, and depending on their extent, severity and frequency, could either amplify or dampen spatial heterogeneity in forest biomass. Here we evaluate spatial variation in the basal area of late-successional Picea abies (L./Karst.) forests across the Carpathian Mountain Range of central Europe and compare the roles of coarse-scale biophysical gradients and natural disturbances in driving that variation across a hierarchy of scales (landscapes, stands, and plots). We inventoried forest composition and structure, and reconstructed disturbance histories using tree cores collected from 472 plots nested within 30 late-successional stands, spanning the Carpathian Mountains (approximately 4.5 degrees of latitude). We used linear mixed-effects models to compare the effect of disturbance regimes and site conditions on stand basal area at three hierarchical scales. We found that the basal area of late-successional Picea abies forests varied across a range of spatial scales, with climatic drivers being most important at coarse scales and natural disturbances acting as the primary driver of forest heterogeneity at fine scales. For instance, the stand-level basal area varied among landscapes, with the highest values (48–68 m
2 ha−1 ) in the warmer southern Carpathian Mountains, and lower values (37–52 m2 ha−1 on average) in cooler areas of the eastern and western Carpathians. Finer-scale variation was driven by local disturbances (mainly bark beetle and windstorms) and the legacies of disturbances that occurred more than a century ago. Our findings suggest that warming could increase the basal area of northern sites, but potential increasing disturbances could disrupt these environmental responses. [ABSTRACT FROM AUTHOR]- Published
- 2019
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22. Differences in micromorphology of the implant–abutment junction for original and third-party abutments on a representative dental implant.
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Fokas, George, Ma, Li, Chronopoulos, Vasilios, Janda, Martin, and Mattheos, Nikos
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Abstract Statement of problem Evidence for micromorphology and precision of fit of third-party prosthetic components compared with the original manufacturer's components is lacking. Purpose The purpose of this in vitro pilot study was to evaluate the micromorphological differences among different commercial brands of zirconia, titanium, and gold abutments for dental implants in terms of tight surface contact. Material and methods The following abutments (n=3 per type) were preloaded on Straumann Bone Level implants according to the manufacturer's instructions for zirconia (Zr, Zr2, Zr3), titanium (Ti and Ti2), and gold (Gold 1, Gold 2). The micromorphology of the implant–abutment units was investigated by using scanning electron microscopy (original magnification ×10 to ×500) after microtome sectioning. After we calibrated, the length of the areas with tight contact (TC) (discrepancy ≤3 μm) was calculated at the level of conical connection (CC), lower internal connection (LIC), and screw threads (STs). The interexaminer agreement was assessed by using intraclass correlation coefficient(s) (ICC). One-way ANOVA was used for the overall comparison of the Zr groups, and the Student paired t test was used for pairwise comparisons of the abutments of the same group. After we adjusted for multiple comparisons, the significance level for the overall and pairwise comparisons of Ti and Gold groups was set at a P value of.008 and a P value of.003 for the Zr groups. Results Major differences were found among the different abutment types in terms of design and extent of surface contact. The TC showed significant differences among the abutments of Zr group, depending on the side and level of evaluation (Zr1 > Zr2 > Zr3 on the left side for CC; Zr1, Zr2 > Zr3 on the right side for CC, and, Zr2 > Zr3 on the right side for LIC; P <.003). In Ti group, no significant differences were found (P >.008). The Gold and Gold 2 groups had significantly greater contact on the left side of CC (P <.008). Conclusions A difference in design of the abutments was apparent. The tight surface contact was significantly different among the examined abutments or abutment screws and the respective area of the inner surface of the implants. [ABSTRACT FROM AUTHOR]
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- 2019
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23. Profile of tree-related microhabitats in European primary beech-dominated forests.
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Kozák, Daniel, Mikoláš, Martin, Svitok, Marek, Bače, Radek, Paillet, Yoan, Larrieu, Laurent, Nagel, Thomas A., Begovič, Krešimir, Čada, Vojtěch, Diku, Abdulla, Frankovič, Michal, Janda, Pavel, Kameniar, Ondrej, Keren, Srđan, Kjučukov, Peter, Lábusová, Jana, Langbehn, Thomas, Málek, Jakub, Mikac, Stjepan, and Morrissey, Robert C.
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ECOLOGICAL niche ,EUROPEAN beech ,BIODIVERSITY ,FOREST restoration ,NOTHOFAGUS solandri - Abstract
Highlights • We compared Tree-related microhabitats (TreMs) in the Dinarides and Carpathians. • Density and diversity of TreMs were very high in beech dominated primary forests. • Geographical region was not a primary driver of TreM profile. • Tree species richness, DBH, and snags were the main drivers of TreM profile. • These findings may provide a benchmark for forest management practices. Abstract Tree-related microhabitats (TreMs) are important features for the conservation of biodiversity in forest ecosystems. Although other structural indicators of forest biodiversity have been extensively studied in recent decades, TreMs have often been overlooked, either due to the absence of a consensual definition or a lack of knowledge. Despite the increased number of TreM studies in the last decade, the role of drivers of TreM profile in primary forests and across different geographical regions is still unknown. To evaluate the main drivers of TreM density and diversity, we conducted the first large-scale study of TreMs across European primary forests. We established 146 plots in eight primary forests dominated by European beech (Fagus sylvatica L.) in the Carpathian and Dinaric mountain ranges. Generalized linear mixed effect models were used to test the effect of local plot characteristics and spatial variability on the density and diversity (alpha, beta, and gamma) of TreMs. Total TreM density and diversity were significantly positively related with tree species richness and the proportion of snags. Root mean square tree diameters were significantly related to alpha and gamma diversity of TreMs. Both regions reached similarly high values of total TreM densities and total TreM densities and diversity were not significantly different between the two regions; however, we observed between the two regions significant differences in the densities of two TreM groups, conks of fungi and epiphytes. The density and diversity of TreMs were very high in beech-dominated mountain primary forests, but their occurrence and diversity was highly variable within the landscapes over relatively short spatial gradients (plot and stand levels). Understanding these profile provides a benchmark for further comparisons, such as with young forest reserves, or for improving forest management practices that promote biodiversity. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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24. More ways than one: Mixed-severity disturbance regimes foster structural complexity via multiple developmental pathways.
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Meigs, Garrett W., Morrissey, Robert C., Bače, Radek, Chaskovskyy, Oleh, Čada, Vojtěch, Després, Tiphaine, Donato, Daniel C., Janda, Pavel, Lábusová, Jana, Seedre, Meelis, Mikoláš, Martin, Nagel, Thomas A., Schurman, Jonathan S., Synek, Michal, Teodosiu, Marius, Trotsiuk, Volodymyr, Vítková, Lucie, and Svoboda, Miroslav
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TEMPERATE forests ,FOREST canopies ,FOREST ecology ,ECOLOGICAL disturbances ,FOREST regeneration - Abstract
Mixed-severity disturbance regimes are prevalent in temperate forests worldwide, but key uncertainties remain regarding the variability of disturbance-mediated structural development pathways. This study investigates the influence of disturbance history on current structure in primary, unmanaged Norway spruce ( Picea abies ) forests throughout the Carpathian Mountains of central and eastern Europe, where windstorms and native bark beetle outbreaks are the dominant natural disturbances. We inventoried forest structure on 453 plots (0.1 ha) spanning a large geographical gradient (>1,000 km), coring 15–25 canopy trees per plot for disturbance history reconstruction (tree core total n = 11,309). Our specific objectives were to: (1) classify sub-hectare-scale disturbance history based on disturbance timing and severity; (2) classify current forest structure based on tree size distributions (live, dead, standing, downed); (3) characterize structural development pathways as revealed by the association between disturbance history and current forest structural complexity. We used hierarchical cluster analysis for the first two objectives and indicator analysis for the third. The disturbance-based cluster analysis yielded six groups associated with three levels of disturbance severity (low, moderate, and high canopy loss) and two levels of timing (old, recent) over the past 200 years. The structure-based cluster analysis yielded three groups along a gradient of increasing structural complexity. A large majority of plots exhibited relatively high (53%) or very high (26%) structural complexity, indicated by abundant large live trees, standing and downed dead trees, and spruce regeneration. Consistent with conventional models of structural development, some disturbance history groups were associated with specific structural complexity groups, particularly low-severity/recent (very high complexity) and high-severity/recent (moderate complexity) disturbances. In other cases, however, the distribution of plots among disturbance history and structural complexity groups indicated either divergent or convergent pathways. For example, multiple disturbance history groups were significantly associated with the high complexity group, demonstrating structural convergence. These results illustrate that complex forest structure – including features nominally associated with old-growth – can be associated as much with disturbance severity as it is with conventional notions of forest age. Because wind and bark beetles are natural disturbance processes that can induce relatively high levels of tree mortality while simultaneously contributing to structural complexity and heterogeneity, we suggest that forest management plans allow for the stochastic occurrence of disturbance and variable post-disturbance development trajectories. Such applications are especially appropriate in conservation areas where biodiversity and forest resilience are management objectives, particularly given projections of increasing disturbance activity under global change. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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25. Simulation of Severe Accident Scenarios in Nuclear Containments.
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Cervenka, Jan, Janda, Zdenek, Jendele, Libor, Pukl, Radomir, and Cervenka, Vladimir
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COMPUTER simulation ,ACCIDENTS ,NUCLEAR reactors ,REINFORCED concrete ,FINITE element method - Abstract
The paper presents the main theoretical backgrounds and application of FE program ATENA to simulation of severe accident in nuclear structures. The software was developed by Cervenka Consulting, Prague, Czech Republic with the aim to offer a tool for numerical simulation of concrete structures subjected to actions in service, ultimate as well as extreme limit states due to mechanical as well as physical effects. Nonlinear behavior of concrete is modeled by theories of damage and plastic flow [1]. Paper outlines the basic features of the used material model. It demonstrates the model accuracy on results from recent blind prediction competitions [2]. In the last section, it shows examples of simulations of severe accidents scenarios in nuclear power plants structures [4]. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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26. Mixed-severity natural disturbances promote the occurrence of an endangered umbrella species in primary forests.
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Mikoláš, Martin, Svitok, Marek, Bollmann, Kurt, Reif, Jiří, Bače, Radek, Janda, Pavel, Trotsiuk, Volodymyr, Čada, Vojtěch, Vítková, Lucie, Teodosiu, Marius, Coppes, Joy, Schurman, Jonathan S., Morrissey, Robert C., Mrhalová, Hana, and Svoboda, Miroslav
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ECOLOGICAL disturbances ,ENDANGERED species ,KEYSTONE species ,HABITATS ,FOREST biodiversity ,DENDROCHRONOLOGY - Abstract
Primary forests are characterized by high vertical and horizontal stand diversity, which provides habitat for a diverse range of species with complex habitat requirements. Detailed knowledge of related ecological processes and habitat development of primary forest species are essential to inform forest management and biodiversity conservation decisions, but relationships are not well documented. We collected dendrochronological data and inventoried numerous structural elements in permanent plots throughout the primary temperate forests within the Carpathian Mountains. We fit and compared multiple predictive models to quantify the importance of 200 years of natural disturbance dynamics on the occurrence probability of an umbrella species – the capercaillie ( Tetrao urogallus ). We showed that a mixed-severity disturbance regime ranging from low through moderate to high severity disturbances is required to generate diverse forest habitats suitable for capercaillie. The variation in natural disturbance severity and its timing promoted key structural habitat elements, such as low natural regeneration density, low mature tree density, high ground vegetation cover, availability of forest gaps, and abundance of standing deadwood. This study demonstrates the importance of natural disturbance in maintaining the variety of conditions necessary to support primary forest specialist species. Managers of protected areas should be mindful that natural disturbances generate habitat for the capercaillie in mountain Norway spruce forests. Further intervention is unnecessary. Conservation planning and forest reserve design should shift focus to the large-scale spatial requirements needed to ensure that a wide range of forest developmental phases are represented in protected areas. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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27. Combining Homogenization, Indentation and Bayesian Inference in Estimating the Microfibril Angle of Spruce.
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Šejnoha, Michal, Janda, Tomáš, Vorel, Jan, Kucíková, Lucie, and Padevěd, Pavel
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ASYMPTOTIC homogenization ,BAYESIAN analysis ,MICROFIBRILS ,WOOD ,ELASTICITY - Abstract
It has been shown that the microfibril angle may severely reduce the longitudinal elastic stiffness of wood. The present paper addresses this issue by combining experimental measurements on various scales, homogenization and Bayesian statistical method. To that end, the variation of effective stiffness as a function of microfibril angle is first estimated by combining nanoindentation and homogenization. The results from a series of tensile tests carried out on thin samples of wood containing only a few growth rings are expected to give additional source of information. In the present study both types of data, microscopic as well as macroscopic measurements, are exploited in the framework of Bayesian inference to get improved, posterior, knowledge of the microfibril angle distribution. Owing to a computational demand associated with the Markov chain Monte Carlo method, as the engine of the updating process, the homogenization based on classical micromechanics is adopted. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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28. The historical disturbance regime of mountain Norway spruce forests in the Western Carpathians and its influence on current forest structure and composition.
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Janda, Pavel, Trotsiuk, Volodymyr, Mikoláš, Martin, Bače, Radek, Nagel, Thomas A., Seidl, Rupert, Seedre, Meelis, Morrissey, Robert C., Kucbel, Stanislav, Jaloviar, Peter, Jasík, Marián, Vysoký, Juraj, Šamonil, Pavel, Čada, Vojtěch, Mrhalová, Hana, Lábusová, Jana, Nováková, Markéta H., Rydval, Miloš, Matějů, Lenka, and Svoboda, Miroslav
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NORWAY spruce ,ECOLOGICAL disturbances ,FOREST dynamics ,LANDSCAPE ecology ,ECOLOGICAL resilience ,ECOSYSTEM dynamics ,BIODIVERSITY - Abstract
In order to gauge ongoing and future changes to disturbance regimes, it is necessary to establish a solid baseline of historic disturbance patterns against which to evaluate these changes. Further, understanding how forest structure and composition respond to variation in past disturbances may provide insight into future resilience to climate-driven alterations of disturbance regimes. We established 184 plots (mostly 1000 m 2 ) in 14 primary mountain Norway spruce forests in the Western Carpathians. On each plot we surveyed live and dead trees and regeneration, and cored around 25 canopy trees. Disturbance history was reconstructed by examining individual tree growth trends. The study plots were further aggregated into five groups based on disturbance history (severity and timing) to evaluate and explain its influence on forest structure. These ecosystems are characterized by a mixed severity disturbance regime with high spatiotemporal variability in severity and frequency. However, periods of synchrony in disturbance activity were also found. Specifically, a peak of canopy disturbance was found for the mid-19th century across the region (about 60% of trees established), with the most important periods of disturbance in the 1820s and from the 1840s to the 1870s. Current stand size and age structure were strongly influenced by past disturbance activity. In contrast, past disturbances did not have a significant effect on current tree density, the amount of coarse woody debris, and regeneration. High mean densities of regeneration with height >50 cm (about 1400 individuals per ha) were observed. Extensive high severity disturbances have recently affected Central European forests, spurring a discussion about the causes and consequences. We found some evidence that forests in the Western Carpathians were predisposed to recent severe disturbance events as a result of synchronized past disturbance activity, which partly homogenized size and age structure and made recent stands more vulnerable to bark beetle outbreak. Our data suggest that these events are still part of the range of natural variability. The finding that regeneration density and volume of coarse woody debris were not influenced by past disturbance illustrates that vastly different past disturbance histories are not likely to change the future trajectories of these forests. These ecosystems currently have high ecological resilience to disturbance. In conclusion, we suggest that management should recognize disturbances as a natural part of ecosystem dynamics in the mountain forests of Central Europe, account for their stochastic occurrence in management planning, and mimic their patterns to foster biodiversity in forest landscapes. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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29. The legacy of disturbance on individual tree and stand-level aboveground biomass accumulation and stocks in primary mountain Picea abies forests.
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Trotsiuk, Volodymyr, Svoboda, Miroslav, Weber, Pascale, Pederson, Neil, Klesse, Stefan, Janda, Pavel, Martin-Benito, Dario, Mikolas, Martin, Seedre, Meelis, Bace, Radek, Mateju, Lenka, and Frank, David
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NORWAY spruce ,PLANT biomass ,BIOACCUMULATION in plants ,MOUNTAIN forests ,FOREST ecology ,TREE growth - Abstract
Disturbances, both natural and human induced, influence forest dynamics, ecosystem functioning, and ecosystem services. Here, we aim to evaluate the consequences of natural disturbances on the magnitude and dynamics of tree- and stand-level biomass accumulation from decadal to centennial scales. We use tree-ring data from 2301 trees and biometric data from 4909 trees sampled in 96 plots (each 1000 m 2 ) to quantify the influence of mixed severity disturbance regimes on annual aboveground biomass increment (AGBI) and total aboveground biomass accumulation (AGB) across a mountainous monotypic Norway spruce ( Picea abies (L.) Karst.) primary forest. We hypothesise that the multiple internal and external factors constraining tree growth will cause differences in tree and stand-level biomass trajectories in these natural forests. Although we found that tree-level AGB growth increases with tree size, we also found that tree age and disturbance legacies plays a crucial role for AGB in the investigated Norway spruce forests. Importantly, while younger trees of the same diameter class have an average current AGBI rate that is ∼225% higher than older trees (300–400 years), we find trees that have been suppressed for up to 120 years can respond vigorously when competition is reduced. On average, post disturbance AGBI was ∼400% greater than pre-disturbance AGBI. Growth of suppressed trees, independent of their age, followed similar trajectories after canopy accession. While aboveground biomass generally increased through time, the time since disturbance and disturbance severity are important co-predictors for stand-level AGBI and AGB. These forests regained most of the above ground living biomass over short interval (∼50 years) after low intensity disturbances. The highest stand-level living AGB was observed on plots that experienced >40% canopy removal 160–190 years ago, whereas the highest AGBI occurred in plots disturbed recently within the past 40–50 years. Our results emphasize the importance of including both individual tree age and disturbance legacies to accurately characterize biomass dynamics and trajectories in forest ecosystems. Importantly, the period of time that a tree is in the canopy, and not tree age, modulates the trajectory of tree level AGBI. Growth rates begin to decline after ∼30 years (tree-rings width) and ∼100 years (AGBI) in the canopy. We demonstrate that even late-seral forests can rapidly regain biomass lost to low intensity disturbance. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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30. Frequent severe natural disturbances and non-equilibrium landscape dynamics shaped the mountain spruce forest in central Europe.
- Author
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Čada, Vojtěch, Morrissey, Robert C., Michalová, Zuzana, Bače, Radek, Janda, Pavel, and Svoboda, Miroslav
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LANDSCAPE changes ,SPRUCE ,FORESTS & forestry ,MOUNTAINS ,CLIMATE change ,IPS typographus - Abstract
Disturbances shape forest structure and composition, but the temporal dynamics of disturbance patterns, their influence on dynamics of forest structural complexity, and the potential impacts of ongoing climate changes are not fully understood. We addressed these issues by focusing on (1) long-term, landscape level retrospective analysis of disturbance dynamics of mountain Norway spruce ( Picea abies ) forest; (2) testing for the prevailing disturbance agent; and (3) the detection of disturbance drivers, particularly site conditions, using a dendrochronological approach. We had a unique opportunity to sample a large area of natural forest (in otherwise altered region) in Bohemian Forest, that was recently affected by extensive and severe wind and bark beetle disturbances raising management concerns. Tree-ring series of a minimum of 35 trees on each of the 26 study plots were analysed for signals of past disturbances that were indicated either by release from suppression (rapid growth increase) or rapid early growth rate (gap origin). A broad range of disturbance severities were detected across the landscape, but severe disturbances (>50% trees responded), with a short rotation period of 174 years, best characterize the area. Reconstructed disturbances were associated with historically documented windstorms and bark beetle outbreaks. They were distributed across the landscape and affected its large portions with spatially variable severity. Over the last five centuries, disturbances peaked in the 1820s, but were rare after 1880. This non-equilibrium dynamics resulted into mature landscape structure at the end of 20th century and contributed to the large extent of disturbances in the last two decades. Disturbances were more frequent on wind-exposed locations such as mountain ridges and flatter terrain. Frequent disturbances did not allow the forest to develop into an old-growth phase; rather disturbance events of variable severities created structures important for biodiversity and could also preserve key early-seral phases in the landscape. We anticipate that potential future increase of disturbance intensities will not lead to comparable regime shifts in forests shaped by high-severity disturbances that kill largely mature trees (e.g., wind and bark beetle), because such disturbances are followed by resistant forest structure. Conservation areas should be large enough to allow for a wide range of disturbances. Emphasizing ecological functions needs understanding of biological legacies of natural disturbances and managers could partly rely on natural events to restore natural features into cultivated forests. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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31. Measuring inaccuracy of uncertain doxastic states in many-valued logical systems.
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Janda, Pavel
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ERROR analysis in mathematics ,PHILOSOPHY of mathematics ,MATHEMATICAL models of uncertainty ,MATHEMATICAL analysis ,ORDERED pairs - Abstract
I will propose an alternative philosophical approach to the representation of uncertain doxastic states. I will argue that the current account of measuring inaccuracy of uncertain doxastic states is inadequate for Belnap's four-valued logic. Specifically, a situation can be found in which either an inaccuracy measure returns a completely wrong result or an agent's inaccuracy score is inadequate relative to the mistake in her doxastic attitude. This will motivate an alternative representation of uncertain doxastic states based on ordered pairs. I will describe a possible inaccuracy measure that is suitable for ordered pairs, and I will show that it has all the qualities that are required for an inaccuracy measure to be legitimate. Finally, I will introduce conditions of rationality for uncertain doxastic states represented by ordered pairs. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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32. Disturbance history drives current compositional and diversity patterns of primary Picea abies (L.) Karst. forest vegetation.
- Author
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Koutecký, Tomáš, Ujházy, Karol, Volařík, Daniel, Ujházyová, Mariana, Máliš, František, Gömöryová, Erika, Bače, Radek, Ehrenbergerová, Lenka, Glončák, Peter, Hofmeister, Jeňýk, Homolák, Marián, Janda, Pavel, Koutecká, Věra, Koutecký, Petr, Lvončík, Samuel, Mikoláš, Martin, and Svoboda, Miroslav
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SILVER fir ,PLANT diversity ,FOREST plants ,UNDERSTORY plants ,TRAFFIC violations ,NORWAY spruce ,SPRUCE - Abstract
• The understorey of primary spruce forests is shaped by historical disturbances. • Plant diversity is affected by time since the last disturbance and its severity. • Severe disturbances in 1860–1890 resulted in recent stands with poor understorey. • K content in soil, canopy and Vaccinium cover mediate effect of disturbances. Development of primary spruce forests is driven by a series of disturbances, which also have an important influence on the understorey vegetation and its diversity. Early post-disturbance processes have been intensively studied, however, very little is known about the long-term effects of disturbances on the understorey. We quantified disturbance history using dendrochronological methods to investigate its impact on vascular plant diversity and understorey species composition. We sampled 141 plots randomly assigned throughout primary stands located in the zone of natural montane acidophilous forests dominated by Picea abies (L.) Karst. in the Western Carpathians. Dendrochronological, dendrometric, and environmental parameters were related to understorey properties using ordination methods and a Bayesian approach using multilevel linear models (GLMM). Time since the last disturbance (23–260 years ago; mostly windstorms and bark beetle outbreaks) had a significant effect on understorey species composition of the current communities, and it also interacted with disturbance severity to influence species diversity. The effect of disturbances on the understorey was largely mediated by the alteration of stand structure (age, DBH, canopy openness), Vaccinium myrtillus L. cover, and topsoil chemical properties. A period of severe disturbances between 1860 and 1890 resulted in a legacy of our current, relatively homogeneous spruce stands with less diverse sciophilous understorey dominated by V. myrtillus , which is in contrast to heterogeneous stands (in terms of age and spatial structure) driven by small-scale, lower-severity disturbances, which led to an understorey enriched by species with higher demands on light and topsoil quality (higher K concentration and lower C/N ratio). All developmental pathways following disturbances create a unique complex of spatiotemporal understorey variability in the montane spruce forests. Therefore, to preserve their full diversity, disturbances of all severities and sizes should be accepted as natural drivers, both in the field of nature conservation and close-to-nature forestry efforts. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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33. Age, competition, disturbance and elevation effects on tree and stand growth response of primary Picea abies forest to climate.
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Primicia, Irantzu, Camarero, Jesús Julio, Janda, Pavel, Čada, Vojtĕch, Morrissey, Robert C., Trotsiuk, Volodymyr, Bače, Radek, Teodosiu, Marius, and Svoboda, Miroslav
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PLANT growth ,NORWAY spruce ,CLIMATE change ,TREE height ,FOREST management ,COMPETITION (Biology) - Abstract
Stands and trees may exhibit different climate–growth responses compared to neighbouring forests and individuals. The study of these differences is crucial to understanding the effects of climate change on the growth and vulnerability of forests and trees. In this research we analyse the growth responsiveness of primary Norway spruce forests to climate as a function of different stand (elevation, aspect, slope, crowding, historic disturbance regime) and tree (age, tree-to-tree competition) features in the Romanian Carpathians. Climate–growth relationships were analysed using Pearson correlation coefficients between ring-width indices (RWIs) and climate variables. The influence of stand and tree characteristics on the RWI responses to climate were investigated using linear mixed-effects models. Elevation greatly modulated the climate–growth associations and it frequently interacted with competition intensity or tree age to differentially influence growth responsiveness to climate. Old trees were more sensitive to climate than young trees, but while old tree’s response to climate highly depended on elevation (e.g. positive influence of summer temperature on old trees’ RWIs at high elevations, but negative effect at low elevations), differences of the young trees’ response across the elevation gradient were less evident. The severity of the past disturbance also modified the climate–growth associations because of contrasting canopy structures. Our results suggest that although an increase in temperature might enhance growth at high elevations, it may also induce growth declines due to drought stress at lower elevations, particularly for old trees or trees growing under high levels of competition, which may increase their vulnerability to disturbances. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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34. Carbon pools in a montane old-growth Norway spruce ecosystem in Bohemian Forest: Effects of stand age and elevation.
- Author
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Seedre, Meelis, Kopáček, Jiří, Janda, Pavel, Bače, Radek, and Svoboda, Miroslav
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MOUNTAIN forests ,NORWAY spruce ,FORESTS & forestry ,FOREST productivity ,MOUNTAIN ecology - Abstract
Good understanding of forest productivity and carbon (C) storage capacity is essential for better understanding of C dynamics and climate modeling. Studies of old-growth forest C dynamics from central and eastern Europe are rare and the few remaining pristine forests represent a unique opportunity to study natural forest dynamics in an otherwise managed landscape. We studied protected old-growth Norway spruce ( Picea abies L.) stands in the Bohemian Forest, Czech Republic, to explore total ecosystem C pool (live and dead biomass and soil) variability in forest ecosystem as a function of stand age and elevation. These old-growth forest ecosystems store very high amounts of C, up to 570 t C ha −1 , and 393 t C ha −1 on average. Live biomass is the dominant C pool followed by mineral soil, forest floor and dead biomass. We found that total C significantly decreased with increasing elevation (1025–1338 m a.s.l) from 456 to 294 t C ha −1 , predominantly driven by decreases in live biomass and forest floor C pools. Significant changes take place in individual pools based on age and elevation gradients, but total C was not significantly different between stands age 116–145 years. Contrary to some recent findings that old-growth forest ecosystems continue to sequester C long after maturity, our data supports the hypothesis that old-growth forests reach a steady state and become C neutral. They accumulate same amount of C through photosynthesis than is lost by decay and leaching. This study provides a detailed overview of C pools of old-growth Bohemian Forests and highlights the importance of including all major C pools in forest ecosystem C studies. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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35. A mixed severity disturbance regime in the primary Picea abies (L.) Karst. forests of the Ukrainian Carpathians.
- Author
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Trotsiuk, Volodymyr, Svoboda, Miroslav, Janda, Pavel, Mikolas, Martin, Bace, Radek, Rejzek, Jan, Samonil, Pavel, Chaskovskyy, Oleh, Korol, Mykola, and Myklush, Stepan
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NORWAY spruce ,FORESTS & forestry ,PLANT development ,LANDSCAPES ,CLIMATE change ,FOREST management - Abstract
Natural disturbance regimes play key roles in shaping forest structure and development at stand and landscape levels. Disturbances are commonly complex and variable, such that classical dichotomous characterization of disturbance regimes as following large infrequent disturbances or patch dynamics is too simplistic, especially when the resulting damage is more severe than the baseline of a single tree patch dynamic, but not severe enough to represent large infrequent disturbance. Ongoing climate change affects mountain Picea abies forests in Central, East and Southeastern Europe by an increasing frequency of storms and bark beetle outbreaks. We present a unique study based on extensive dataset aimed to reveal the spatiotemporal pattern of the disturbance history and role of the mixed severity disturbances in primary spruce mountain forest landscapes in the Ukrainian Carpathians. We reconstructed canopy disturbance history and maximum disturbance severity using ca. 2396 tree cores in 96 sample plots. Neither large-scale stand-replacement nor fine scale dynamics was the prevailing disturbance over the last four centuries. Rather, we observed a complex spatiotemporal pattern of mixed severity disturbances. Canopy turnover time ranged between 50 and 300 years and depended on the maximum severity of the disturbance event. Spatial analyses revealed no similarity in spatiotemporal pattern across disturbance histories or maximum disturbance severities. We observed evidence of a combination of variable severity disturbances that fails to fit the classical scheme of gap or patch dynamics with sharply defined sizes and borders, but is more consistent with a mixed severity disturbance regime across the landscape. Windstorms were likely the most important past disturbance agent. The probability of an epidemic bark beetle attack was low, although the possibility of small local outbreaks cannot be excluded. An additional, potentially overlooked, agent of disturbance could be historic periods of extreme cold. This reconstructed disturbance regime may challenge existing silvicultural systems in the Carpathians, calling for a more complex spatiotemporal forest management approach. However, mimicking a mixed severity disturbance regime can be done at the forest management level by applying a range of disturbance severities at the stand level. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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36. Spatial and temporal extents of natural disturbances differentiate deadwood-inhabiting fungal communities in spruce primary forest ecosystems.
- Author
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Ferenčík, Matej, Svitok, Marek, Mikoláš, Martin, Hofmeister, Jeňýk, Majdanová, Linda, Vostarek, Ondřej, Kozák, Daniel, Bače, Radek, Begovič, Krešimir, Běťák, Jan, Čada, Vojtěch, Dušátko, Martin, Dvořák, Daniel, Frankovič, Michal, Gloor, Rhiannon, Janda, Pavel, Kameniar, Ondrej, Kříž, Martin, Kunca, Vladimír, and Markuljaková, Katarína
- Subjects
FUNGAL communities ,FOREST biodiversity ,FOREST resilience ,FOREST protection ,ECOSYSTEMS ,SPECIES diversity ,FOREST conservation - Abstract
• Historical disturbances shaped the contemporary local and regional richness of fungi. • Natural disturbances had contrasting effects on fungi at different spatial scales. • Local red-listed species diversity increased due to higher disturbance frequency. • Regional diversity of all species was decreased by higher disturbance severity. Understanding the processes shaping the composition of assemblages at multiple spatial scales in response to disturbance events is crucial for preventing ongoing biodiversity loss and for improving current forest management policies aimed at mitigating climate change and enhancing forest resilience. Deadwood-inhabiting fungi represent an essential component of forest ecosystems through their association with deadwood decomposition and the cycling of nutrients and carbon. Although we have sufficient evidence for the fundamental role of deadwood availability and variability of decay stages for fungal species diversity, the influence of long-term natural disturbance regimes as the main driver of deadwood quantity and quality has not been sufficiently documented. We used a dendroecological approach to analyse the effect of 250-years of historical natural disturbance and structural habitat elements on local (plot-level) and regional (stand-level) species richness of deadwood-inhabiting fungi. We used data collected from 51 study plots within nine best-preserved primary spruce forest stands distributed across the Western Carpathian Mountains. Historical disturbances shaped the contemporary local and regional species richness of fungi, with contrasting impacts of disturbance regime components at different spatial scales. While local diversity of red-listed species has increased due to higher disturbance frequency, regional diversity of all species has decreased due to higher severity historical disturbances. The volume of deadwood positively influenced the species richness of deadwood-inhabiting fungi while canopy openness had a negative impact. The high number of observed rare species highlights the important role of primary forests for biodiversity conservation. From a landscape perspective, we can conclude that the distribution of species from the regional species pool is - at least to some extent - driven by past spatiotemporal patterns of disturbance events. Natural disturbances occurring at higher frequencies that create a mosaic forest structure are necessary for fungal species - especially for rare and endangered taxa. Thus, both the protection of intact forest landscapes and forest management practises that emulate natural disturbance processes are recommended to support habitats of diverse fungal communities and their associated ecosystem functions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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- View/download PDF
37. Three hundred years of spatio-temporal development in a primary mountain Norway spruce stand in the Bohemian Forest, central Europe.
- Author
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Janda, Pavel, Svoboda, Miroslav, Bače, Radek, Čada, Vojtěch, and Peck, JeriLynn E.
- Subjects
NORWAY spruce ,FOREST dynamics ,FOREST mapping ,FOREST canopies ,DENDROCHRONOLOGY - Abstract
The model of developmental dynamics has grown in recent years to include the role of disturbances, but few studies have examined fine-scale spatio-temporal dynamics. We present a unique study from mountain Norway spruce ( Picea abies (L.) Karst.) forests in central Europe to evaluate the role of disturbances in spatio-temporal tree distribution patterns. We established three one-hectare permanent study plots (PSP) in an old-growth mountain Norway spruce forest in a strictly protected nature reserve in central Europe. We mapped the spatial positions of all trees >1.3 m in height and extracted increment cores of all canopy trees >6 m in height. Disturbance chronologies were reconstructed based on dendroecological approaches indicating disturbance events from: (1) abrupt increases in radial growth (release) and (2) intensive juvenile growth (open canopy recruitment). Spatio-temporal patterns were detected using Moran’s I. Recruitment and canopy accession were discontinuous over time. Synchronous radial growth release events were observed during 1750–1770 and 1810–1830 and synchronous new recruitment was observed in 1770–1800. Most of the detected disturbances could be associated with historical records of strong winds or bark beetle outbreaks of moderate severity. Most trees ascended into the canopy via open canopy recruitment and many formed distinct patches (about 20–50 m in diameter) with a similar date of canopy accession. Our study provides evidence of a mixed historical disturbance regime including large-scale infrequent moderate intensity disturbance combined with frequent low severity events. These disturbances created large-scale synchronous periods of recruitment and canopy accession. The resulting developmental model indicates a complex spatio-temporal pattern of tree death and establishment across a large range of patch sizes. For ecologically based management systems we suggest the application of mixed harvest intensities at different spatial and temporal scales to better replicate natural disturbance patterns and associated legacies. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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38. Influence of the Cutting Edge Radius and the Cutting Edge Preparation on Tool Life and Cutting Forces at Inserts with Wiper Geometry.
- Author
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Fulemova, Jaroslava and Janda, Zdeněk
- Subjects
CUTTING tools ,SURFACE roughness ,STEAM-turbines ,GRINDING & polishing ,WORKPIECES ,MILLING-machines - Abstract
Abstract: This article deals with the influence of cutting edge preparation and cutting edge radius on tool life, cutting forces and the roughness of machined surface. The cutting edge preparation was done on the inserts with wiper geometry which are used during machining of dividing plane at a steam turbine casing. This cutting inserts were prepared by the technology of grinding, drag finishing and laser technology. The edge radius for drag finished tools was 5, 10 and 15μm and for laser treated tool 5μm. The workpiece material was ferrite – martensite steel with the content of 9%Mo and 1%Cr and the material of cutting inserts was submicron sintered carbide. There was used only one cutting insert in the milling cutter. [Copyright &y& Elsevier]
- Published
- 2014
- Full Text
- View/download PDF
39. Early-onset pulmonary and cutaneous vasculitis driven by constitutively active SRC-family kinase HCK.
- Author
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Kanderova, Veronika, Svobodova, Tamara, Borna, Simon, Fejtkova, Martina, Martinu, Vendula, Paderova, Jana, Svaton, Michael, Kralova, Jarmila, Fronkova, Eva, Klocperk, Adam, Pruhova, Stepanka, Lee-Kirsch, Min Ae, Hornofova, Ludmila, Koblizek, Miroslav, Novak, Petr, Zimmermannova, Olga, Parackova, Zuzana, Sediva, Anna, Kalina, Tomas, and Janda, Ales
- Abstract
Inborn errors of immunity are genetic disorders characterized by various degrees of immune dysregulation that can manifest as immune deficiency, autoimmunity, or autoinflammation. The routine use of next-generation sequencing in the clinic has facilitated the identification of an ever-increasing number of inborn errors of immunity, revealing the roles of immunologically important genes in human pathologies. However, despite this progress, treatment is still extremely challenging. We sought to report a new monogenic autoinflammatory disorder caused by a de novo activating mutation, p.Tyr515∗, in hematopoietic cell kinase (HCK). The disease is characterized by cutaneous vasculitis and chronic pulmonary inflammation that progresses to fibrosis. Whole-exome sequencing, Sanger sequencing, mass spectrometry, and western blotting were performed to identify and characterize the pathogenic HCK mutation. Dysregulation of mutant HCK was confirmed ex vivo in primary cells and in vitro in transduced cell lines. Mutant HCK lacking the C-terminal inhibitory tyrosine Tyr522 exhibited increased kinase activity and enhanced myeloid cell priming, migration and effector functions, such as production of the inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α, and production of reactive oxygen species. These aberrant functions were reflected by inflammatory leukocyte infiltration of the lungs and skin. Moreover, an overview of the clinical course of the disease, including therapies, provides evidence for the therapeutic efficacy of the Janus kinase 1/2 inhibitor ruxolitinib in inflammatory lung disease. We propose HCK-driven pulmonary and cutaneous vasculitis as a novel autoinflammatory disorder of inborn errors of immunity. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
40. Comparative Pooled Survival and Revision Rate of Austin-Moore Hip Arthroplasty in Published Literature and Arthroplasty Register Data.
- Author
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Sadoghi, Patrick, Thaler, Martin, Janda, Wolfgang, Hübl, Michael, Leithner, Andreas, and Labek, Gerold
- Abstract
Abstract: The aim was to evaluate the pooled survival and revision rate of Austin-Moore hip arthroplasty (AMHA) in published literature and arthroplasty register data. A comprehensive literature analysis of clinical publications and register reports was conducted with the main endpoints revision surgery and revision rate. Sixteen relevant clinical studies have been found to significantly underestimate revision rates by a ratio of 2.15 compared to register data sets. The medium-term outcome of AMHA showed significantly worse outcomes than the use of other bipolar implants, or modular cervicocephalic prostheses and data of journal publications on revision rates deviate significantly from data of arthroplasty registers. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
41. Advances in Skin Cancer Early Detection and Diagnosis.
- Author
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Loescher, Lois J., Janda, Monika, Soyer, H. Peter, Shea, Kimberly, and Curiel-Lewandrowski, Clara
- Abstract
Objectives: To provide an overview of 1) traditional methods of skin cancer early detection, 2) current technologies for skin cancer detection, and 3) evolving practice models of early detection. Data Sources: Peer-reviewed databased articles and reviews, scholarly texts, and Web-based resources. Conclusion: Early detection of skin cancer through established methods or newer technologies is critical for reducing both skin cancer mortality and the overall skin cancer burden. Implications for Nursing Practice: A basic knowledge of recommended skin examination guidelines and risk factors for skin cancer, traditional methods to further examine lesions that are suspicious for skin cancer and evolving detection technologies can guide patient education and skin inspection decisions. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
42. Dendrochronological reconstruction of the disturbance history and past development of the mountain Norway spruce in the Bohemian Forest, central Europe.
- Author
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Čada, Vojtěch, Svoboda, Miroslav, and Janda, Pavel
- Subjects
NORWAY spruce ,DENDROCHRONOLOGY ,ECOLOGICAL disturbances ,PLANT development ,FOREST ecology ,FOREST management ,PLANT mortality ,PLANT growth - Abstract
Abstract: Disturbances play a major role in shaping forest structure and composition. However, the effects of disturbances on forest ecosystems in central Europe are poorly understood, despite the importance of this information for forest management (e.g., for managing recent, large-scale, high-severity disturbances in the region). Using the tree-ring approach, this work investigates the past development, disturbance history and historical range of variability of the old mountain Norway spruce (Picea abies) forest stand in the high elevation Bohemian Forest (Protected Landscape Area Šumava) in the Czech Republic. The goals of the study were threefold: (1) to reconstruct the historical disturbances of the forest, (2) to describe the recruitment strategy of trees in response to disturbance, and (3) to describe the subsequent development of trees by their growth trends. We cored all stems within three 0.25ha plots. The growth series were surveyed for events indicative of past tree mortality: (1) abrupt, sustained and rapid increases in growth (releases from suppression) and (2) rapid early growth rates (gap origins). We then conducted a cluster analysis of individual growth trends by fitting splines to the power-transformed and age-filtered (RCS-method) tree ring series. High-severity disturbances were identified in the 1820s and 1860s. Less severe disturbances also occurred every 10–50years. The disturbances were synchronised among plots and consistent with data from distant locations in the Bohemian Forest. Most disturbances were explained by known historical windstorms; some by bark beetle outbreaks. Most trees regenerated shortly before or after disturbance and exhibited evidence of 1–3 disturbance events in their growth chronologies. A smaller proportion of trees was suppressed before disturbance for more than 10years. The cluster analysis of growth trends revealed five types of tree behaviour classified according to their growth rate during (1) stand initiation and (2) later development. We conclude that disturbances (including large, high-severity and low-frequency disturbances) contribute to the broad range of variability of central European mountain spruce forests. Sustainable management strategies should therefore incorporate described disturbances and their biological legacies, as many species likely depend on them. In addition, the development trajectory of stands following stand-replacing disturbance, as described here, can be used to predict future development of presently disturbed stands. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
43. Natural regeneration in Central-European subalpine spruce forests: Which logs are suitable for seedling recruitment?
- Author
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Bače, Radek, Svoboda, Miroslav, Pouska, Václav, Janda, Pavel, and Červenka, Jaroslav
- Subjects
REGENERATION (Botany) ,MOUNTAIN plants ,SPRUCE ,FOREST ecology ,LOGGING ,ARMILLARIA ,PHELLINUS ,BARK beetles - Abstract
Abstract: Decaying logs form the major seedbed for trees in European subalpine Picea abies forests. However, many aspects related to seedling colonization pattern on logs remain unclear. The aim of this study was to analyze the relationships of P. abies (Norway spruce) seedling (height <15cm) and sapling (height ⩾15cm) densities on decaying logs in relation to stage of wood decay, log diameter, ground contact of decaying log, assumed cause of tree death, presence of species of wood-decaying fungi and coverage by surrounding plants in the subalpine old-growth forests of the Bohemian Forest and Ash Mountains, in the Czech Republic. We have focused on how logs with different origin differ in their properties and how these properties influence seedling abundance. Seedling densities peaked on the medium-decayed logs and decreased thereafter. Sapling densities continually increased as the decay progressed. Seedling and sapling densities followed negative binomial distributions, with many logs of all decay stages having low regeneration densities. The degree of ground contact, white-rot-causing Armillaria spp. presence, white-rot-causing Phellinus nigrolimitatus presence and log diameter were positively related to both seedling and sapling density. Also tree death as a result of wind uprooting was positively related to sapling density. Conversely, the presence of brown-rot-causing Fomitopsis pinicola and tree death as a result of bark beetle attack were negatively related to regeneration densities. The low cover of vegetation from sides positively affected seedling density; however, heavily covered logs were less occupied by seedlings. Our study provides evidence that large logs originating from wind uprooting or butt rot infection are most appropriate for retention to promote natural spruce regeneration in managed subalpine spruce forests. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
44. A new approach to influence contact angle and surface free energy of resin-based dental restorative materials.
- Author
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Rüttermann, Stefan, Trellenkamp, Taina, Bergmann, Nora, Raab, Wolfgang H.-M., Ritter, Helmut, and Janda, Ralf
- Subjects
DENTAL materials ,CONTACT angle ,SURFACE energy ,DENTAL resins ,OPERATIVE dentistry ,BACTERIAL adhesion ,POLYMERIZATION - Abstract
Abstract: The purpose of the present study was to identify novel delivery systems and active agents which increase the water contact angle and reduce the surface free energy when added to resin-based dental restorative materials. Two delivery systems based on zeolite or novel polymeric hollow beads (Poly-Pore), loaded with two low surface tension active agents (hydroxy functional polydimethylsiloxane and polydimethylsiloxane) or a polymerizable active agent (silicone polyether acrylate) were used to modify commonly formulated experimental dental resin composites. The non-modified resin was used as a standard (ST). Flexural strength, flexural modulus, water sorption, solubility, polymerization shrinkage, surface roughness R
a , contact angle θ, total surface free energy γS , and the apolar γS LW , polar γS AB , Lewis acid γS + and base γS – components, and the active agents surface tensions γL were determined (P <0.05). The active agents did not differ in γL . The modified materials had significantly higher θ but significantly lower γS , γS AB and γS – than the ST. A Poly-Pore/polydimethyl siloxane delivery system yielded the highest θ (110.9±3.5°) acceptable physical properties and the lowest values for γS LW and γS – . Among the modified materials the polymerizable materials containing active agents had the lowest γAB and the highest γS + and γS – . Although not significant, both of the zeolite delivery systems yielded higher γS LW , γS + and γS – but lower γS AB than the Poly-Pore delivery systems. Poly-Pore based delivery systems highly loaded with low surface tension active agents were found not to influence the physical properties but to significantly increase the water contact angle and thus reduce surface free energy of dental resin composites. [Copyright &y& Elsevier]- Published
- 2011
- Full Text
- View/download PDF
45. Telomerase activity and serum levels of p53 protein as prognostic factors of survival in patients with advanced non-small cell lung cancer.
- Author
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Targowski, Tomasz, Jahnz-Rozyk, Karina, Owczarek, Witold, Raczka, Alicja, Janda, Pawel, Szkoda, Tomasz, and Płusa, Tadeusz
- Abstract
Summary: Purpose: Evaluation of relationships between survival time of patients with advanced, non-resectable non-small cell lung cancer (NSCLC) and telomerase activity in aspirates, collected from primary lung tumours, and serum p53 protein levels. Material and methods: The study group consisted of 52 patients with advanced (stage IIIB and IV) non-small cell lung cancer. In all of them, transthoracic fine-needle biopsy (TFNB) of focal pulmonary lesion was performed. The aspirates were subjected to telomerase activity by the PCR–ELISA PLUS method and serum levels of p53 protein were determined by the ELISA method. Additionally, clinical advancement of cancer and the time period of survival were assessed in the studied group. Kaplan–Meyer method and Cox analysis were used for statistical evaluation of survival prognosis. Results: Increased telomerase activity was observed in 42 (81%) of the patients with non-resectable non-small cell lung cancer. Elevated concentrations of serum p53 protein were found in 28 (54%) of the participants. The following death rates were noted during the entire study period: twenty-three (23) (62%), out of 37 patients with increased telomerase activity, 7 (47%), out of 15 without detectable telomerase activity in primary lung tumour, 16 (57%), out of 28 subjects with increased serum levels of p53 protein and 14 (58%), out of 24 with no increased serum levels of p53. A significant relationship was observed in Cox hazard analysis between the time of survival and telomerase activity, while no such relationship was observed between the survival time period and serum p53 protein levels or sex, age, primary lung tumour size, lymph node status or development of distant metastases. Conclusion: Telomerase activity in advanced primary non-small cell lung cancer is a better predictor of patients'' survival than serum levels of p53 protein. The assessment of telomerase activity supplements in the prognosis of survival in the course of non-resectable NSCLC. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
46. Natural development and regeneration of a Central European montane spruce forest.
- Author
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Svoboda, Miroslav, Fraver, Shawn, Janda, Pavel, Bače, Radek, and Zenáhlíková, Jitka
- Subjects
MOUNTAIN plants ,NORWAY spruce ,MOUNTAIN biodiversity ,WINDSTORMS ,BARK beetles ,DENDROCHRONOLOGY ,PLANT mortality ,PLANT growth ,FORESTS & forestry - Abstract
Abstract: Montane Norway spruce forests of Central Europe have a very long tradition of use for timber production; however, recently there has been increasing concern for their role in maintaining biological diversity. This concern, coupled with recent severe windstorms that led to wide-spread bark beetle outbreaks, has brought the management of montane spruce forests to the forefront of public policy discussions in Central Europe. In order to shed light on the natural development and current structure of mature montane spruce forests, we established four 0.25ha research plots in a semi-natural montane spruce forest in the Šumava Mountains (The Bohemian Forest), Czech Republic. We mapped all trees, extracted increment cores for age and growth-pattern analyses, and inventoried all current tree regeneration, including the substrates on which it was found. Stands were characterized by uni-modal tree diameter distributions and high basal areas (56.6m
2 ha−1 on average), indicating a natural transition from the stem exclusion phase towards the understory reinitiation phase. The stands showed largely single-cohort recruitment age structures, however, with recruitment spanning seven decades. Our analyses suggest that this cohort existed as advance regeneration prior to major disturbances in the late 1800s, which included post-bark beetle salvage logging. Spatial pattern analyses of living and dead stems combined, showed an increase in uniformity of living trees, pointing to the role of natural density-dependent mortality. However, past growth patterns and historical documentation suggest that low intensity canopy disturbances (wind and snow) also caused mortality and diversified canopy structure. Because the stands developed naturally over the past 120+ years and thus escaped thinning operations, high volumes of coarse woody debris (94m3 ha−1 ) and snag densities (546stemsha−1 ) have accrued. Advance spruce regeneration was quite abundant and existed primarily on deadwood substrates, even though these occupied only a small percent of stand area. Because of salvage logging in the late 1880s, these stands do not qualify, according to the traditional paradigm, as natural spruce forests. As a result, they are recently subject to active management practices including salvage logging that remove dead and dying trees. Given the importance of deadwood for forest regeneration and recovery from disturbance, as demonstrated in this study, we argue that dead wood removal may limit future natural regeneration in these stands. Thus, the purported benefits of removing dead and dying trees from semi-natural forests must be carefully weighed against the potential detrimental impacts on natural spruce forest regeneration and biodiversity. [Copyright &y& Elsevier]- Published
- 2010
- Full Text
- View/download PDF
47. Historical mixed-severity disturbances shape current diameter distributions of primary temperate Norway spruce mountain forests in Europe.
- Author
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Rodrigo, Ruffy, Pettit, Joseph L., Matula, Radim, Kozák, Daniel, Bače, Radek, Pavlin, Jakob, Janda, Pavel, Mikoláš, Martin, Nagel, Thomas A., Schurman, Jonathan, Trotsiuk, Volodymyr, Vostarek, Ondřej, Frankovič, Michal, Pettit, Jessika M., Buechling, Arne, Čada, Vojtěch, Begovič, Krešimir, Chaskovskyy, Oleh, Teodosiu, Marius, and Saulnier, Mélanie
- Subjects
MOUNTAIN forests ,CURRENT distribution ,FOREST dynamics ,NORWAY spruce ,TREE size ,STRUCTURAL dynamics ,SPRUCE - Abstract
• Current DBH distribution shapes are driven by historical disturbance regimes. • Low-severity disturbances showed a reverse J-shaped diameter distribution. • High-severity disturbance lead to a unimodal diameter distribution. • Time and severity of last disturbance are good predictors of DBH distribution shape. Natural disturbances strongly influence forest structural dynamics, and subsequently stand structural heterogeneity, biomass, and forest functioning. The impact of disturbance legacies on current forest structure can greatly influence how we interpret drivers of forest dynamics. However, without clear insight into forest history, many studies default to coarse assumptions about forest structure, for example, whether forests are even or unevenly aged. The aim of this study was to analyze the effects of past disturbances on the current diameter distributions of Norway spruce (Picea abies (L.) Karst.)-dominated landscapes throughout the Carpathian Mountains. Our dendroecological dataset comprises tree cores from 339 plots (7,845 total tree cores), nested within 28 primary forest stands, known to vary greatly in the severity of historical disturbances. Our analyses revealed that historical disturbances had a strong and significant effect on the current diameter distribution shapes at the plot level. We demonstrated that mixed-severity disturbance regimes were more frequent and create a complex pattern of diameter distributions at the plot and stand scale. Here, we show that high severity disturbance was associated with unimodal diameter distributions, while low and moderate severity was associated with the reverse J-shaped distribution. This is a result of complex disturbance patterns, with structural biological legacies. Our results will have important management implication in the context of tree size heterogeneity, biomass storage, and productivity as influenced by natural disturbances. Lastly, these results demonstrate that structural changes may arise as consequences of changing disturbance regime associated with global change. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
48. Novel nano-particles as fillers for an experimental resin-based restorative material.
- Author
-
Rüttermann, S., Wandrey, C., Raab, W.H.-M., and Janda, R.
- Subjects
BIOMEDICAL materials ,NANOPARTICLES ,SOLUBILITY ,PHYSICAL & theoretical chemistry - Abstract
Abstract: The purpose of this study is to compare the properties of two experimental materials, nano-material (Nano) and Microhybrid, and two trade products, Clearfil AP-X and Filtek Supreme XT. The flexural strength and modulus after 24h water storage and 5000 thermocycles, water sorption, solubility and X-ray opacity were determined according to ISO 4049. The volumetric behavior (ΔV) after curing and after water storage was investigated with the Archimedes principle. ANOVA was calculated with p <0.05. Clearfil AP-X showed the highest flexural strength (154±14MPa) and flexural modulus (11,600±550MPa) prior to and after thermocycling (117±14MPa and 13,000±300MPa). The flexural strength of all materials decreased after thermocycling, but the flexural modulus decreased only for Filtek Supreme XT. After thermocycling, there were no significant differences in flexural strength and modulus between Filtek Supreme XT, Microhybrid and Nano. Clearfil AP-X had the lowest water sorption (22±1.1μgmm
−3 ) and Nano had the highest water sorption (82±2.6μgmm−3 ) and solubility (27±2.9μgmm−3 ) of all the materials. No significant differences occurred between the solubility of Clearfil AP-X, Filtek Supreme XT and Microhybrid. Microhybrid and Nano provided the highest X-ray opacity. Owing to the lower filler content, Nano showed higher shrinkage than the commercial materials. Nano had the highest expansion after water storage. After thermocycling, Nano performed as well as Filtek Supreme XT for flexural strength, even better for X-ray opacity but significantly worse for flexural modulus, water sorption and solubility. The performances of microhybrids were superior to those of the nano-materials. [Copyright &y& Elsevier]- Published
- 2008
- Full Text
- View/download PDF
49. Preparation of the coronal and middle third of oval root canals with a rotary or an oscillating system.
- Author
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Rüttermann, Stefan, Virtej, Anca, Janda, Ralf, and Raab, Wolfgang H.-M.
- Abstract
Objectives: To comparatively evaluate the preparation of oval root canals with a rotary or an oscillating system. Study design: The middle and coronal parts of 55 extracted permanent teeth with oval canals were prepared using FlexMaster (FM) rotary NiTi instruments and EndoEze AET (EE) stainless steel oscillating instruments. Pre- and postoperative images of cross-sections were superimposed to identify shifts in the center and to assess the percentage of untreated regions. In addition, the middle segment was investigated by scanning electron microscope (SEM) to determine debris and smear layer removal. Results: The systems did not significantly differ in the shifts of the canal centers in the middle part of the root. Only a few of the preparations yielded an excellent result with no uninstrumented canal wall left. The SEM investigation demonstrated poor results for both systems regarding debris and smear layer removal, but no significant differences could be observed. Conclusions: Neither FM nor EE was capable of completely preparing oval root canals. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
50. Management of pulmonary aspiration.
- Author
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Janda, Matthias, Scheeren, Thomas W.L., Nöldge-Schomburg, Gabriele F.E., and Nöldge-Schomburg, Gabriele F E
- Subjects
ASPIRATION pneumonia ,GASTRIC acid ,ELECTIVE surgery ,OPERATIVE surgery ,MEDICAL research ,ACUPRESSURE ,DRUG therapy ,MEDICAL protocols ,DIAGNOSIS ,PREVENTION ,THERAPEUTICS - Abstract
Pulmonary aspiration of gastric contents in the perioperative phase is associated with increased postoperative morbidity and mortality. For the management of aspiration, differentiation between acid-associated aspiration pneumonitis and aspiration pneumonia as a consequence of a secondary bacterial contamination is of crucial importance. The incidence of aspiration in elective surgery is 1 per 2000–3000 anaesthesias in adults. In children, it is slightly more common with 1 per 1200–2600 anaesthesias. In the context of emergency anaesthesias the incidence of aspiration is three to four times higher. The risk particularly increases with recent ingestion of solid food or fluids, with older patients, with pregnant women, and with consciousness-reduced patients. Besides giving a review of the pathophysiology, incidence, and the risk factors of aspiration, this article places emphasis on the practical management of this anaesthesia-associated complication. Cricoid pressure, as a non-evidence-based but clinically wide-spread method in the context of the prophylaxis of aspiration, is discussed critically. The main part deals with strategies to structure the management of aspiration by use of scientific concepts based on medical crisis management. For this, an algorithm based on current scientific investigations is presented. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
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